Snowflake ID (Twitter/X)

A Twitter Snowflake is a 64-bit, roughly time-sortable identifier laid out as: 1 unused sign bit, a 41-bit millisecond timestamp offset from a custom epoch (1288834974657 ms, 2010-11-04), a 10-bit machine id (5-bit datacenter + 5-bit worker), and a 12-bit per-millisecond sequence counter. It fits in a signed 64-bit integer and sorts by creation time, which is why it underpins tweet and many other platform ids.

identifier

spec: Twitter Snowflake (twitter-archive/snowflake)

length 64 bits sortable decimal uint64 (commonly carried as a string to avoid 53-bit JS float precision loss)

example:

1541815603606036480

field	bits	meaning
sign	1	Unused/reserved most-significant bit, always 0 so the value is a non-negative signed int64.
timestamp	41	Milliseconds since the Twitter epoch 1288834974657 (2010-11-04 01:42:54.657 UTC).
datacenter_id	5	Datacenter identifier (part of the 10-bit machine id).
worker_id	5	Worker/machine identifier (the other half of the 10-bit machine id).
sequence	12	Per-machine counter incremented for each id within the same millisecond (4096 ids/ms/machine).

Custom epoch: subtract 1288834974657 ms (2010-11-04) from the timestamp field to recover Unix ms; only ~41 bits of time fit, lasting ~69 years from that epoch.
The 10-bit machine id splits as 5-bit datacenter + 5-bit worker in the original Twitter design; other 'snowflake' systems repartition these 10 bits differently.
Because the timestamp is the high-order field, snowflakes sort by creation time. JSON consumers should treat the id as a string; a 64-bit value exceeds JavaScript's 53-bit safe integer range.
Example is an illustrative 19-digit 64-bit snowflake decimal.

provenance

source: https://github.com/twitter-archive/snowflake/tree/snowflake-2010
version: twitter-archive/snowflake @ snowflake-2010 (original release)
retrieved: 2026-05-29 · updated: 2026-05-29T00:00:00Z

per-fact attribution:

ext.bit_layout — https://github.com/twitter-archive/snowflake/tree/snowflake-2010 Original Twitter Snowflake: 41-bit timestamp, 10-bit machine id (5 datacenter + 5 worker), 12-bit sequence, 1 unused sign bit; 64-bit signed.
ext.notes — https://en.wikipedia.org/wiki/Snowflake_ID Second independent source for the field widths and the Twitter custom epoch 1288834974657 ms (2010-11-04).
ext.example — https://developer.x.com/en/docs/x-ids Twitter/X documents that Tweet/user ids are 64-bit snowflakes returned as both int64 and string (id_str) because JS cannot hold the full precision.

Snowflake ID (Twitter/X)

identifier

provenance

see also